SAO PAULO: At least 57 inmates were killed on Monday during a clash between rival factions inside a prison in the northern Brazilian state of Para, authorities said.
The disturbance at the prison in Altamira, 850km (528mi) from Belem, the state capital, lasted for more than five hours and was finally brought under control by the combined efforts of several different law enforcement agencies, the Efe news reported.
Sixteen of the dead were decapitated, while the other 41 died of smoke inhalation after one of the factions set fire to a cell-block.
"It was a localised attack, aimed at exterminating members of a rival faction. They (the aggressors) entered, killed and started a fire," the head of the state prison system, Jarbas Vasconcelos, told the press.
As inmates were sitting down to breakfast in one part of the prison, attackers from another cell-block burst in and set upon their enemies with "homemade weapons", the prison service said.
Two guards taken hostage during the assault were freed later unharmed, while two other people were hospitalised with injuries.
Relatives of some inmates at Altamira mounted protests at the end of the May to press prison officials to transfer members of one of the rival factions to other facilities to avoid conflict.
But according to Vasconcelos, authorities saw no signs of trouble ahead of Monday's eruption.
Though the prison service says that the Altamira penitentiary was built to hold 200 prisoners and currently holds 311, a report from the National Council of Justice shows the facility is home to 343 prisoners - more than double its capacity of 163.
Brazil's overcrowded prisons have been wracked by escalating violence since 2017. In May of this year, 55 inmates were killed in a span of less than 48 hours at four penitentiaries in the Amazonian city of Manaus.